In achalasia, the inlet of the stomach, the cardia, is constricted. Food remains in the esophagus, which thus can considerably distend. The treatment of achalasia consists, in addition to other methods, in pneumatic dilatation (Nanson, E. M., Gastroenterology 51, pp. 236-241, 1966; Vantrappen, G., Hellemans, J., Deloof, W., Valembois, P., Vandenbroucke, Gut 12, pp. 268-275, 1971; Wienbeck, M., Heitman, P., Dtsch. Med. Wschr. 98, pp. 814-825, 1973). Pneumatic dilatation is characterized by its simplicity and high success rate.
In pneumatic dilatation, an inflatable balloon is introduced into the esophagus of man. It is pushed into the constricted segment, for instance, the cardia, and is inflated there to widen the constriction. It is necessary to limit the diameter of the balloon to an upper value so that the balloon does not assume too great dimensions above and/or below the constricted segment in the esophagus or stomach. With a known pneumatic dilatator this is achieved by surrounding the balloon, which can be inflated from the outside of the human body, by a cloth bag. This cloth bag in turn is surrounded by a protective balloon. The cloth bag limits the dilatator to a certain diameter during the inflation.
The presently known balloon dilatators have a number of disadvantages. First of all, the manufacturing process of a dilatator, consisting of three layers (balloon, cloth bag, balloon), is rather elaborate and expensive. Particularly the incorporation of the cloth bag can lead to complications. In addition, such a dilatator may be rather sensitive to damage. Under certain circumstances, problems may also arise in cleaning and re-use. Finally, it is a significant disadvantage that the known dilatators are not introduced and dilated under the direct supervision of a physician, but by an indirect control method, namely under X-ray control. In the blind introduction of the instrument, perforations and thus unfortunate complications occur in 2 to 9% of all cases, as observations have shown.
In the advanced stage of achalasia with a twisted esophagus, it is usually not possible to push the dilatator of the known design into the constricted cardia. This difficulty has been overcome, in certain circumstances, by letting the patient swallow a guide thread on the day preceding this treatment, the thread being weighted with a bag containing a contrast medium, such as barium sulfate, which may be seen in X-ray pictures. For dilatation, the guide thread, which has advanced into the lower intenstinal segment, is tightened, and a flexible guide wire is pushed along it. The dilatator is then introduced over this guide wire. It can be readily seen that such a procedure is inconvenient both for the physician and for the patient.